Yes, you can machine an AR receiver from a billet, and there are some people over on AR15.com who have posted threads detailing there builds, but the easiest way is to use a 80% forging. You can get jigs that will allow it to be completed with a sturdy drill press and taps, or a mill.
I always found AR’s to be easier to build from scratch than an AK because there’s no pressing or riviting to build an AR, just simple machining.
ah, I see that someone else already beat me to the point.
thanks for trying to keep me out of jail, anyway. I have never gotten the courage up to try a “from scratch” AR build. AKs are much easier, as they are designed to be built by a 14 year old illiterate Somalian.
I love mine though. I shoot tighter groups with milsurp ammo at and iron sights at 100 yards with my MAK-90 than with my Rock River AR.., again using Wolf steelcase milsurp (replacement extractors are cheap).